moderator
Quick Summary
A moderator in a nuclear reactor is a substance that slows down fast neutrons emitted during nuclear fission. This slowing down process, called down-scattering, increases the probability that these neutrons will cause further fission events, thus sustaining a chain reaction. Common moderators include light water, heavy water, graphite, and beryllium, with water and heavy water also serving as coolants in many reactors. The core of a nuclear reactor contains the fuel, cladding, coolant, and moderator, with fission energy being produced in this central region. Moderators are crucial for thermal reactors, which operate with slow, or thermal, neutrons.1234
- nuclear reactor - Coolants and moderators
- nuclear reactor - Fuel types
- nuclear reactor - Reactor control elements
- nuclear reactor - Reactor control
- nuclear reactor - Thermal , intermediate, and fast reactors
- nuclear fission - Fission chain reactions and their control
- nuclear fission - Structure and stability of nuclear matter
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nuclear reactorCoolants and moderatorsA variety of substances, including light water, heavy water, air, carbon dioxide, helium, liquid sodium, liquid sodium-potassium alloy, and hydrocarbons (oils), have been used as coolants. Such substances are, in
Read MoreA variety of substances, including light water, heavy water, air, carbon dioxide, helium, liquid sodium, liquid sodium-potassium alloy, and hydrocarbons (oils), have been used as coolants. Such substances are, in
Read More- nuclear reactorThermal, intermediate, and fast reactors
…reactor and are known as moderators. Since water and heavy water also can function as coolants, they perform a dual purpose in thermal reactors. (See below Coolants and moderators.)
Read More…reactor and are known as moderators. Since water and heavy water also can function as coolants, they perform a dual purpose in thermal reactors. (See below Coolants and moderators.)
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